//****************************************************************
// Autor:   Yimy Juarez 
//       
// Seccion: 10
// Nombre del Archivo: Stack.java
// Fecha de Modificacion:17/07/2012
// Descripcion:
// Modelado de interfaz Stack
// ***************************************************************
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package hojatrabajo2;

/**
 *
 * @author tomado de la clase se Algoritmos y ED
 */
public interface Stack<E> {
    /**
     *
     * @param item the value of item
     */
    public void push(E item);
   // pre: 
   // post: item is added to stack
   // will be popped next if no intervening push
   
    /**
     *
     */
    public E pop();
   // pre: stack is not empty
   // post: most recently pushed item is removed and returned
   
    /**
     *
     */
    public E peek();
   // pre: stack is not empty
   // post: top value (next to be popped) is returned
   
    /**
     *
     *
     * @return the boolean
     */
    public boolean empty();
   
    /**
     *
     * @return the int
     */
    public int size();
   // post: returns the number of elements in the stack
}
